Skip to main content
Loading…
Appendix 1. Critical Areas Reporting Requirements
This appendix is included in your selections.

The following information is required to be submitted for sites containing critical areas.

A. General Information (required for all critical areas).

1. Name of proposal as shown on City applications.

2. Name of applicant as shown on City applications.

3. Name of organization and individual providing this information.

4. List any technical expertise/special qualifications of person providing this information.

5. Date the information was prepared.

6. Location of the proposed activity (street address and tax parcel number), including a vicinity map.

7. Clearly identify the development proposal being addressed, including City file number and key project drawing references (originator of drawings, originator’s reference number if shown on the drawings, sheet numbers, revision numbers and dates for each sheet, and include reduced copies of key drawings in the report).

8. Give a succinct but inclusive description of the existing site, including acreage and current and past uses on the property.

9. A copy of an aerial photo with overlays displaying site boundaries and critical areas.

10. A single map showing all critical areas at one inch equals 20 feet scale, depicting:

a. Identified critical areas and required buffers;

b. Limits of any areas to be disturbed;

c. Site boundary property lines and roads;

d. Rights-of-way and easements;

e. Existing physical improvements (buildings, fences, impervious surfaces, utilities, etc.);

f. Contours at two-foot intervals;

g. All natural and manmade features within the maximum buffer area of any critical area on or near the site (in no case less than a minimum 50 feet from the site).

11. A statement specifying the accuracy of the report and key project specific assumptions made and relied upon. List recommendations, if any, for further reporting regarding critical areas related to the proposed project as the project proceeds.

12. Provide a bibliography of published information referenced, including maps and best available science materials.

a. For sites with mitigation, also provide the following information identified in 13 through 17 below. (Information in this section is to be provided only if there are critical areas within or in the vicinity of the site that will be impacted by the proposed project.)

13. A summary description of reasonable efforts made to apply mitigation sequencing pursuant to RZC 21.64.010.L, Mitigation Standards, Criteria, and Plan Requirements, to avoid, minimize, and mitigate impacts to critical areas.

14. Plans for adequate mitigation, as needed, to offset any impacts, including but not limited to:

a. The impacts to on-site and affected off-site critical areas; and

b. The impacts of any proposed alteration of a critical area or buffer on the development proposal, other properties, and the environment.

15. A listing of applicable performance standards and a summary of how each applicable performance standard was addressed. (See RZC 21.64.010.M, Performance Standards for Mitigation Planning.)

16. A discussion of ongoing management practices that will protect the critical area after the project site has been developed, including proposed monitoring and maintenance programs.

17. Additional information may be required. The Technical Committee may require additional information to be included in the critical areas report when deemed necessary to the review of the proposed activity.

B. Fish and Wildlife Habitat Conservation Areas Reporting Requirements (includes streams). A fish and wildlife habitat conservation areas report shall be prepared by a qualified professional who is a biologist with experience preparing reports for the relevant type of habitat.

1. Wildlife Report Requirements (in addition to the General Information listed in Appendix 1.A above).

a. A wildlife report must be submitted to the City for review. The purpose of the report is to determine the extent, function, and value of wildlife habitat on any site where regulated activities are proposed. The report will also be used by the City to determine the sensitivity and appropriate classification of the habitat, appropriate wildlife management requirements, and potential impacts of proposed activities. The information required by this report should be coordinated with the study and reporting requirements for any other critical areas located on the site.

b. The report shall include the following information:

i. A map drawn at an engineering scale of one inch equals 20 feet of vegetative cover types, reflecting the general boundaries of different plant communities on the site.

ii. A description of the species typically associated with the cover types, including an identification of any species of concern, priority species, and species of local importance that might be expected to be found.

iii. The results of searches of DNR’s Natural Heritage and Non-Game Data System databases.

iv. The result of searches of the Washington Department of Wildlife Priority Habitat and Species database.

v. Habitat Assessment. A habitat assessment is an investigation of the project area to evaluate the presence or absence of a potential (listed) fish or wildlife species of concern or habitat. A fish and wildlife habitat conservation area report shall contain a written assessment of habitats, including the following site and proposal related information at a minimum:

A. General site conditions, including topography, waterbodies, and wetlands.

B. Detailed description of vegetation on and adjacent to the project area.

C. Identification of any areas that have previously been disturbed or degraded by human activity or natural processes.

D. The layers, diversity, and variety of habitat found on the site.

E. Identification of edges between habitat types and any species commonly associated with that habitat.

F. The location of any migration or movement corridors.

G. A narrative summary of existing habitat functions and values.

H. Identification of any species of local importance, priority species, threatened, sensitive, or candidate species that have a primary association with the habitat on or adjacent to the project area, and assessment of potential impacts to the use of the site by the species.

I. A discussion of any local, state, or federal management recommendations, including Washington Department of Fish and Wildlife habitat management recommendations, that have been developed for species or habitats located on or adjacent to the project area.

J. Identification of any core preservation areas that are on or adjacent to the site. See RZC 21.64.020.A.2.a, Core Preservation Areas, for areas considered core preservation areas. Map and describe these areas.

K. Identification of any quality habitat areas that are on the site. See RZC 21.64.020.A.2.c for areas considered quality habitat areas. Map and describe these areas. This shall include an analysis of size, community diversity, interspersion, continuity, forest vegetation layers, forest age, and invasive plants.

L. A summary of proposed habitat alterations and impacts and proposed habitat management program. Potential impacts may include but are not limited to clearing of vegetation, fragmentation of wildlife habitat, expected decreases in species diversity or quantity, changes in water quality, increases in human intrusion, and impacts on wetlands or water resources.

M. A discussion of measures, including avoidance, minimization, and mitigation, proposed to preserve the existing habitats and restore any habitat that was degraded prior to the current proposed land use activity and to be constructed in accordance with RZC 21.64.010.L, Mitigation Standards, Criteria, and Plan Requirements.

vi. Habitat Unit Assessment Forms. One completed form is required for each habitat unit identified on-site.

vii. Additional Information. When appropriate due to the type of habitat or species present, or the project area conditions, the Technical Committee may also require the habitat management plan to include:

A. An evaluation by an independent qualified professional regarding the applicant’s analysis and the effectiveness of any proposed mitigating measures or programs to include any recommendations as appropriate.

B. A request for consultation with the Washington Department of Fish and Wildlife or the local Native American Indian tribe.

C. Detailed surface and subsurface hydrologic features both on and adjacent to the site.

2. Stream Reconnaissance Report Requirements (in addition to the General Information listed in Appendix 1.A above). A stream reconnaissance report shall be prepared by a qualified stream biologist or stream ecologist.

a. A stream reconnaissance report must be submitted to the City for review. The purpose of the report is to determine the physical and biological characteristics and functions and values of streams on any site where regulated activities are proposed. The report will also be used by the City to establish appropriate buffer requirements. The information required for this report should be coordinated with the study and reporting requirements established for any other critical areas located on the site.

b. The ordinary high water mark shall be flagged in the field by a qualified consultant. Field flagging must be distinguishable from other survey flagging on the site. The field flagging must be accompanied by a stream reconnaissance report.

c. The report shall include the following information:

i. Streams Map. Stream ordinary high water marks (OHWM) shall be located on a site map with an engineering scale of one inch equals 20 feet. The map must show:

A. Surveyed locations of all stream OHWMs on the property;

B. Hydrologic mapping showing patterns of water movement into, through, and out of the site area.

ii. Stream Reconnaissance Report. A written stream reconnaissance report which includes the following information:

A. A written stream assessment. This assessment shall describe specific descriptions of streams, including stream classification, gradient and flow characteristics, stream bed condition, stream bank and slope stability, presence of fish or habitat for fish, presence of obstruction to fish movement, general water quality, stream bank vegetation, and stream buffer requirements.

B. A written characterization of the riparian corridor. This characterization shall include analysis of the stream buffer to provide the following key functions: shade and temperature regulation, flood conveyance, water quality protection and pollutant removal, nutrient cycling, sediment transport, bank stabilization, woody debris recruitment, wildlife habitat, and microclimate control.

C. A written summary of existing stream value for fisheries habitat, including special consideration for anadromous fisheries. This shall include a discussion on the stream’s potential for salmonid and non-salmonid fish use. Parameters to be analyzed include, but are not limited to, distance of bank full width, channel gradient, size of contributing upstream areas, and fish passage obstructions, if any.

D. A written discussion of measures including avoidance, minimization, and mitigation to preserve the existing riparian corridor and restore areas that were degraded prior to the current proposed land use activity. This shall include a summary of proposed stream and buffer alterations, impacts, and the need for the alterations as proposed. Potential impacts may include but are not limited to vegetation removal, stream bed and stream bank alterations, alteration of fisheries habitat, changes in water quality, and increases in human intrusion. If alteration of a stream is proposed, a stream mitigation plan is required according to the standards of RZC 21.64.020.D, Alteration of Riparian Stream Corridors and 21.64.020.F, Riparian Stream Corridor Performance Standards.

iii. Stream summary sheet.

C. Wetland Reporting Requirements. (In addition to the General Information listed in Appendix 1.A above). A wetland report shall be prepared by a qualified professional who is a certified wetland scientist or a wetland biologist.

1. A wetland report must be submitted to the City for review. The purpose of the report is to determine the extent, characteristics, functions, and values of any wetlands located on a site where regulated activities are proposed. The report will also be used by the City to determine the appropriate wetland rating and to establish appropriate buffer requirements. The information required by this report should be coordinated with the study and reporting requirements for any other critical areas located on the site.

2. Wetland boundaries must be staked and flagged in the field by a qualified consultant employing the currently approved federal manual and supplements. Field flagging must be distinguishable from other survey flagging on the site. The field flagging must be accompanied by a wetland delineation report. Transects shall be required for all wetland identifications, regardless of size. Note that wetland determinations made during the late summer months (July – September) and early fall (September – October) may lack a wetland water regime due to low precipitation. A “wet weather” evaluation may be required.

3. The report shall include the following information:

a. Wetland Map. Wetlands shall be located on a site map with an engineering scale of one inch equals 20 feet. The map must show:

i. Delineated wetland boundary and required buffers.

ii. Hydrologic mapping showing patterns of water movement into, through, and out of the site area.

iii. Location of all test holes and vegetation sample sites, numbered to correspond with flagging in the field and field data sheets.

b. Site designated on a National Wetland Inventory Map (U.S. Fish and Wildlife Service) and a City of Redmond Wetland Inventory Map.

c. Wetland Delineation Report. A written wetland delineation report which includes the following information:

i. Delineation methodology, with special emphasis on whether the approach used was routine, intermediate, or comprehensive, as described in the currently approved federal manual and supplements. This shall include an explanation of how the wetland boundary was determined. The explanation shall identify assumptions made and provide clarification of “close calls.”

ii. A written wetland assessment. This assessment shall describe specific descriptions of wetlands, including wetland category, classification using the USFWS (Cowardin) Method, vegetative, faunal and hydrologic characterization, soil and substrate conditions, wetland acreage, and required buffers.

iii. A written wetland characterization and wetland functions assessment. Wetland characterizations shall use the Wetland Rating System for Western Washington. This characterization identifies the wetland category. The wetland category and “score” shall be part of the description for each wetland. This characterization shall include an analysis of the wetland’s ability to provide the following key functions: provide wildlife, plant, and fisheries habitat; moderate runoff volume and flow rates; reduce sediment, chemical nutrient, and toxic pollutants; provide shading to maintain desirable water temperatures; reduce erosion; and reduce groundwater and surface water pollution. A wetland functions assessment shall be completed for each wetland to establish a baseline that provides a semi-qualitative description for each wetland. A functions assessment must evaluate existing conditions and conditions after development without mitigation. Those functions assessments found acceptable by the Department of Ecology and best available science include the Washington Function Assessment Method and the Linear Method.

iv. A summary of proposed wetland and buffer alterations, impacts, and the need for the alterations as proposed. This shall include a mitigation sequencing analysis. Potential impacts may include but are not limited to loss of flood storage potential, loss of wildlife habitat, expected decreases in species diversity or quantity, changes in water quality, increases in human intrusion, and impacts on associated wetland or water resources. If wetland impacts are proposed, a wetland mitigation plan is required according to the standards of RZC 21.64.010.M, Performance Standards for Mitigation Planning.

d. Field data sheets from the currently approved federal manual and supplements, numbered to correspond with sample site locations as staked and flagged in the field. This includes Data Form 1: Routine Wetland Determination.

e. Wetland rating forms for each wetland as identified in the Washington State Wetland Rating System for Western Washington.

f. Wetland summary sheet.

D. Frequently Flooded Areas Reporting Requirements. (In addition to the General Information listed in Appendix 1.A above). A frequently flooded area report shall be prepared by a qualified professional who is a hydrologist, or engineer, who is licensed in the State of Washington with experience in preparing flood hazard assessments.

1. A frequently flooded area report must be submitted to the City for review for Shorelines of the State (and other watercourses if specifically requested in the review process). The purpose of this report is to ensure the development complies with City of Redmond and Federal Emergency Management Agency (FEMA) requirements and guidelines. The report must include the following site and proposed related information at a minimum:

a. Floodplain Map. Floodplains shall be located on a site map with an engineering scale of one inch equals 20 feet. The map must show the following:

i. The location of the FEMA 100-year floodplain, the “Built Out” 100-year floodplain, the FEMA floodway, and the zero-rise floodway.

ii. All proposed development within the Built Out 100-year floodplain.

iii. Elevation of the lowest floor (including basements and excavated crawl spaces) of all structures.

iv. Location of and proposed grading for compensatory floodplain storage, if required per RZC 21.64.040.C.2.a.

b. Flood Hazard Summary. A written flood hazard summary shall be provided that includes the following:

i. Descriptions and engineering calculations that support the locations of the 100-year FEMA and zero-rise floodplains within the site (see guidelines below).

ii. Descriptions and engineering calculations that support the locations of the 100-year FEMA and zero-rise floodways within the site (see guidelines below).

iii. A statement to verify that fill and structures will not be located within floodways.

iv. Verification that any proposed changes (including utilities, plantings, walkways, etc.) within the floodways will not affect the hydraulic capacities of the floodways. Supporting calculations will be required if changes are proposed in the floodways.

v. Verification that hydraulically equivalent compensating storage is provided if such storage is required for the site per RZC 21.64.040.C.2.a.

2. Locating the Edge of the Floodplain for a Site. This section provides a method to locate the edge of the floodplain for a site so as to conform to detailed topographic mapping at a site plan scale. The basic approach is to use elevations of the water surface at flood stage and project the elevations along cross sections until they intersect with the site scale topographic map. The resulting floodplain defined for the site must be checked by engineering calculations to verify adequate conveyance with no increase in the flood stage water surface elevations for the floodplain. Include the following for both the FEMA and zero-rise floodplains:

a. Appropriate data from current floodplain studies and maps, including flood profiles, selected cross section locations, flood elevations for each cross section, and base flood discharge(s).

b. Actual field topography with appropriate contours for the entire floodplain within the site plus the floodplain on the opposite side of the stream plus the floodplain upstream and downstream of the site for at least 100 feet.

c. Cross section locations on the site topography map showing intersections of the flood elevations with the topographic elevations. These intersection points are then connected, using topographic information, to outline the floodplain.

d. Verification, by hydraulic calculations, that the base flood discharge can be accommodated within the defined floodplain and within the flood elevations. (Contact Development Services for level of calculations required.)

e. Proposed topographic adjustments, based on site-specific situations, to provide adequate hydraulic capacity if hydraulic calculations do not verify such capacity which are acceptable to the Technical Committee.

3. Locating the Current Floodway Limits for a Site. This section provides a way to apply and adjust the floodway maps for a site. The adopted floodway maps are official documents. Changes to the FEMA map generally require FEMA approval. Both FEMA and the City recognize, however, that more detailed site-scale topography and the difficulties in scaling the floodway map dictate that map refinements must frequently be done when working at the site plan scale. Include the following for both the FEMA and zero-rise floodways:

a. An appropriate section of the current floodplain maps enlarged to site plan scale. The section of the map needs to include the entire site, the entire floodplain on the opposite side of the stream, and the floodplain 100 feet upstream and downstream of the site.

b. Appropriate data from current floodway studies, including flood profiles, selected cross section locations, flood elevations for each cross section, and base flood discharges.

c. Actual field topography with appropriate contours for the entire floodplain within the site plus the floodplain on the opposite side of the stream plus the floodplain upstream and downstream of the site for at least 100 feet. Show cross section locations on this topographic map.

d. Location of the floodway limits from the enlarged floodway map on the topographic map.

e. Adjustments to the floodway location as required to reconcile the site topography and the flood profiles. Clearly identify all proposed adjustments.

f. Verification that the floodway study discharge can be accommodated within the floodway (including adjustments approved by the Technical Committee) and within regulatory water surface elevations and velocities.

E. Geologically Hazardous Areas Reporting Requirements. (In addition to the General Information listed in Appendix 1.A above). A geologically hazardous areas report shall be prepared by a geotechnical engineer or geologist, licensed in the State of Washington, with experience analyzing geologic, hydrologic, and groundwater flow systems; or by a geologist who earns his or her livelihood from the field of geology and/or geotechnical analysis, with experience analyzing geologic, hydrologic, and groundwater flow systems, who has experience preparing reports for the relevant type of hazard.

1. A geologically hazardous area report must be submitted to the City. The purpose of this report is to evaluate the actual presence of geologic conditions giving rise to geologic hazards; determine the appropriate class of hazard, according to the classification of potential hazards contained in these regulations; evaluate the safety and appropriateness of proposed activities; and recommend appropriate construction practices, monitoring programs and other mitigation measures required to ensure achievement of the purpose and intent of these regulations. The information required by this report should be coordinated with the study and reporting requirements for any other critical areas located on the site.

2. The approach of the City of Redmond critical area regulations is to require a level of study and analysis commensurate with potential risks associated with geologic hazards on particular sites and for particular proposals. Depending on the particular geologic hazard, geologic, hydrologic, and/or topographic studies may be required. At a minimum, all applicants shall review the history of the site and conduct a surface reconnaissance.

3. Geologically Hazardous Area Report. The geologically hazardous area report shall include the following information:

a. Geologically Hazardous Areas Map. Geologic hazards shall be located on a site map with an engineering scale of one inch equals 20 feet. The map must show the surveyed locations of all geologic hazards and their required buffers/setbacks. In addition, the map must show topography at two-foot intervals.

b. A written geologically hazardous area report which includes the following information:

i. A written geologic hazards characterization. This characterization shall describe specific descriptions of geologic hazards present on-site, including topography; a characterization of soils, geology, and drainage; a characterization of groundwater conditions, including the presence of any public or private wells within one quarter mile of the site; and groundwater elevation, gradient and direction data, including depth and duration of seasonally high water table if any proposed grading, borings, pilings, or excavation work may extend to groundwater depth; identification of any areas that have previously been disturbed or degraded by human activity or natural processes; and a site history.

ii. A written analysis of proposed clearing, grading and construction activities, including construction scheduling; potential direct and indirect, on-site and off-site impacts from development, including dewatering activities. The analysis shall include identification of proposed mitigation measures, including any special construction techniques, monitoring or inspection program, erosion or sedimentation programs (during and after construction), and surface water management and protection controls.

c. Critical Landslide Hazard Areas (Steep Slopes). In addition to the geologically hazardous area report required above, the following tasks and information are required for critical landslide hazard areas.

i. Review site history and available information.

ii. Conduct a surface reconnaissance of the site and adjacent areas.

iii. Conduct subsurface exploration suitable to site and proposal to assess geohydrologic conditions.

iv. Conduct detailed slope stability analysis.

v. Recommend detailed surface water management controls during construction and operation.

vi. Establish recommendations for site monitoring and inspection during construction.

vii. Recommended minimum steep slope buffer distance(s). In no case, shall the setback be less than that required by RZC 21.64.060.B, Landslide Hazard Area Buffers.

d. Critical Erosion Hazard Areas. In addition to the geologically hazardous area report required above, the following tasks and information are required for critical erosion hazard areas:

i. Review site history and available information.

ii. Conduct a surface reconnaissance of the site and adjacent areas.

iii. Identify surface water management, erosion, and sediment controls appropriate to the site and proposal.

e. Seismic Hazard Areas. In addition to the geologically hazardous area report required above, the following tasks and information are required for seismic hazard areas:

i. For one- and two-story single-family structures, conduct an evaluation of site response and liquefaction potential based on the performance of similar structures under similar foundation conditions.

ii. For all other proposals, conduct an evaluation of site response and liquefaction potential, including sufficient subsurface exploration to provide a site coefficient (S) for use in the static lateral force procedure described in the International Building Code.

F. Critical Aquifer Recharge Areas (Wellhead Protection) Reporting Requirements. (In addition to the General Information listed in Appendix 1.A above and the general information listed in Appendix 1.E above). A critical aquifer recharge areas report shall be prepared by a qualified professional who is a hydrogeologist, geologist, or engineer, who is licensed in the State of Washington and has experience in preparing hydrogeologic assessments.

1. A critical aquifer recharge area report must be submitted to the City. The purpose of the report is to evaluate the actual presence of geologic conditions giving rise to the critical aquifer recharge area; determine the appropriate wellhead protection zone; evaluate the safety and appropriateness of proposed activities; and recommend appropriate construction practices, monitoring programs, and other mitigation measures required to ensure achievement of the purpose and intent of these regulations. The information required by this report should be coordinated with the study and reporting requirements for any other critical areas located on the site.

2. The approach of the City of Redmond critical area regulations is to require a level of study and analysis commensurate with potential risks to wellhead protection areas associated with particular sites and particular proposals. Geologic, hydrologic, and/or topographic studies may be required. At a minimum, all applicants shall review the history of the site and conduct a surface reconnaissance.

3. Hydrologic Assessment Required. For all proposed activities to be located in a critical aquifer recharge area, a critical aquifer recharge area report shall contain a level one hydrological assessment. A level two hydrogeologic assessment shall be required for any of the following proposed activities:

a. Activities that result in 5,000 square feet or more impervious site area.

b. Activities that divert, alter, or reduce the flow of surface or groundwaters, including dewatering or otherwise reduce the recharging of the aquifer.

c. The storage, handling, treatment, use, production, recycling, or disposal of deleterious substances or hazardous materials, other than household chemicals used according to the directions specified on the packaging for domestic applications.

d. The use of injection wells, including on-site septic systems, except those domestic septic systems releasing less than 14,500 gallons of effluent per day and that are limited to a maximum density of one system per one acre.

e. Any other activity determined by the Technical Committee likely to have an adverse impact on groundwater quality or quantity, or on the recharge of the aquifer.

4. Written Level One Hydrogeologic Assessment. A level one hydrogeologic assessment shall include the following site and proposal related information at a minimum:

a. information regarding geologic and hydrogeologic characteristics of the site, including the surface location of all critical aquifer recharge areas located on-site or immediately adjacent to the site, and permeability of the unsaturated zone.

b. Groundwater depth, flow direction, and gradient based on available information.

c. Currently available data on wells and springs within 1,300 feet of the project area.

d. Location of other critical areas, including surface waters, within 1,300 feet of the project site.

e. Available historic water quality data for the area to be affected by the proposed activity.

f. Best management practices proposed to be utilized.

5. Written Level Two Hydrogeologic Assessment. A level two hydrogeologic assessment shall include the following site and proposal-related information at a minimum, in addition to the requirements for a level one hydrogeological assessment:

a. Historic water quality and elevation data for the area to be affected by the proposed activity compiled for at least the previous five-year period.

b. Groundwater monitoring plan provisions.

c. Discussion of the effects of the proposed project on the groundwater quality and quantity, including:

i. Predictive evaluation of groundwater withdrawal effects on nearby wells and surface water features.

ii. Predictive evaluation of contaminant transport based on potential releases to groundwater.

iii. Predictive evaluation of groundwater (recharge, elevation, dewatering feasibility, constructability, discharge permitting, etc.) on the proposed project.

d. Identification of the type and quantities of any deleterious substances or hazardous materials that will be stored, handled, treated, used, produced, recycled, or disposed of on the site, including but not limited to materials, such as elevator lift/hydraulic fluid, hazardous materials used during construction, materials used by the building occupants, proposed storage and manufacturing uses, etc.

e. Proposed methods of storing any of the above substances, including containment methods to be used during construction and/or use of the proposed facility.

f. Proposed plan for implementing RZC 21.64.050.D.3.f, Protection Standards During Construction.

g. A spill plan that identifies equipment and/or structures that could fail, resulting in an impact. Spill plans shall include provisions for regular inspection, repair, and replacement of structures and equipment that could fail.

h. A complete discussion of past environmental investigations, sampling, spills, or incidents that may have resulted in or contributed to contaminated soil or groundwater at the site. Attach copies of all historical and current reports, and sampling results.

G. Stream and Wetland Mitigation Plans. Conceptual Mitigation Plan. The applicant shall submit a conceptual mitigation plan, prepared by a qualified consultant, when filing for entitlement or plat approval. The plan must have adequate detail to demonstrate that impacts can be mitigated such that they achieve no net loss of functions and values. The conceptual mitigation plan/report shall include:

1. Executive Summary of CAO Report. Prepare executive summary for the plan. Summarize the project, its impacts, and the proposed mitigation, if required. This may be a one-half to two-page summary of the plan contents, depending on the complexity of the project and the length of the plan. Please include the following items in the Executive Summary:

a. Applicant name, address, and telephone number.

b. Consultant and consultant contact information.

c. Brief description of the proposed development project (include City file number and key drawing references).

d. Location of work (street address, tax parcel number, STR [section, township, and range]).

e. A vicinity map.

f. Description of critical areas.

g. Wetland information, including:

i. (square feet);

ii. Cowardin classification;

iii. Hydrogeomorphic (HGM) classification;

iv. Required buffers; and

v. A brief summary of functions, if applicable.

h. Stream Information, including:

i. Classification;

ii. Downstream connections; and

iii. A brief justification of stream classification if different from the current City of Redmond Stream Classification Map or if unmapped.

i. Description of the measures taken to avoid and minimize impacts to critical areas (i.e., demonstrate that mitigation sequencing was followed).

j. Description of unavoidable wetland impacts and the proposed compensatory mitigation (e.g., restoration, creation, enhancement, and /or preservation), including:

i. Size;

ii. Cowardin classification;

iii. Hydrogeomorphic (HGM) classification;

iv. Wetland rating, if applicable;

v. Required buffers;

vi. A brief summary of functions, if applicable; and

vii. Mitigation ratios used.

k. Description of unavoidable impacts to other aquatic resources and the proposed compensatory mitigation (e.g., stream, lakes, and wildlife).

l. Details about the proposed mitigation project, including:

i. Goals and objectives;

ii. Proposed improvements to the functions and environmental processes of the larger watershed;

iii. Proposed buffers for the compensatory mitigation site (width and total area);

iv. Maintenance frequency;

v. Monitoring period and frequency; and

vi. Potential adaptive management measures resulting from monitoring conclusions.

2. Assessment of Impacts. The purpose of this section of the document is to describe how the development project will affect wetlands and other aquatic resources. A development project can have long-term temporary, short-term temporary, and indirect and/or direct impacts to wetlands and other aquatic resources. Describe all types of impacts. Provide detailed documentation on how wetland and other aquatic resources will be adversely affected at the proposed development site, including the following:

a. Area of wetland/stream impacts;

b. Description of water regime (stream, lakes, rivers, wetlands, subsurface flow, etc.), including:

i. of the source of water to the wetland being affected by the development project. If several sources are present, estimate the percentage contribution from each;

ii. Description of hydrologic regime of the wetland being affected (i.e., rough, qualitative estimation of duration and frequency of inundation and/or saturation. Use generally accepted terms, such as permanent open water, seasonally flooded, seasonally saturated, wet pasture, etc.); and

iii. Map of the surface and groundwater flowing into the impacted area with the direction of water flow indicated.

c. Description of the soils, including:

i. Description of the soil characteristics of the wetland being affected, including soil type and classification; and a description of texture, color, structure, permeability, and organic content;

ii. Soil survey map; and

iii. Map showing soil sampling locations (typically the location of the soil pits used for delineation).

d. Description of the vegetation in and around critical areas, including qualitative descriptions of the different Cowardin (1979) classes of the wetland being affected (include subclass and water regime modifiers). If a forested class is present, also estimate the average age of the canopy species.

e. An estimate of the relative abundance of dominant and subdominant plants within each Cowardin class, using information collected during routine delineation unless more detailed data are available.

f. List of the wetland indicator status of dominant and subdominant species, including:

i. Description of the prevalence and distribution of nonnative and/or invasive species, if any are present at the wetland being affected; and

ii. General description of upland plant communities within 330 feet of the wetland, stream or lake being affected, if any; and

iii. List of rare plants and plant communities that are known to occur on the development project site or adjacent properties. If any of these species are observed on the site, include descriptions of the occurrence and any potential impacts to them. Please include Department of Natural Resources database search results.

g. Description of fauna using the site, including:

i. Description of the animals (including amphibians) using the wetland and buffer being affected. In most cases, a list of species likely to use the habitats on the site is sufficient, with brief descriptions of the existing habitats. Note species seen and amount of time spent looking for on-site wildlife; and

ii. Include a description of federal- and state-listed endangered, threatened, sensitive, and candidate animal species that are known to occur in the general area of the development site, as well as observations of such species. Also, include those listed as “Priority Species” or “Species of Concern” by the Washington State Department of Fish and Wildlife (see http://wdfw.wa.gov/hab/phspage.htm and http://wdfw.wa.gov/wlm/diversity/soc/concern.htm).

h. Position and functions of the wetland(s)/stream(s) in the landscape, including:

i. Class of the wetland and/or stream classification being affected by the development. Use the hydrogeomorphic classification (class and subclass) to describe its position in the watershed. Note downstream receiving waters, if any;

ii. Qualitative description of the functions performed by the wetland and/or stream being affected relative to the position in the watershed. This may include its role in attenuating flooding, as a corridor for wildlife between different regions of the watershed, as part of a regional flyway, or in improving water quality regionally; and

iii. Description of the sampling and assessment methods used.

i. Description of the functions provided by the wetland(s)/stream(s), including:

i. Description of the functions provided by the wetland and/or stream being affected and to what level they are performed (e.g., the site provides the function “Removing Sediment” at a high level, the score for “Removing Sediment” that results from applying (name the method) is X, with X being the highest score that can be achieved); and

ii. Qualitative or quantities, description of the characteristics that enable the wetland and/or stream being affected to perform specific functions, depending on the method used.

j. Wetland rating and/or stream classifications, including:

i. The category of the wetland being affected and/or the classification of stream being affected using the City’s Critical Areas Ordinance (CAO); and

ii. If applicable, copies of the original data sheets used to rate the wetland.

k. Information concerning buffers, including:

i. Size (width) of the undeveloped Critical Areas Ordinance (CAO) required upland buffer being affected by the development project;

ii. Qualitative description of the dominant vegetation in the buffer and the physical structure of plants in it; and

iii. Maps of the buffer areas and the vegetation types.

l. Water quality information, including:

i. Description of any known water quality problems at the development site and whether they will continue after the development project is completed; and

ii. Assessment of whether the development project is expected to worsen or improve existing water quality conditions.

3. Proposed Mitigation Sites. The following information must be provided concerning proposed mitigation sites:

a. Location, including map showing the location of site in relation to the project impact site;

b. Site ownership (current and future);

c. Site selection rationale, including a discussion of how the site fits with the environmental needs in the watershed. If watershed or regional planning efforts exist for the area, explain how the selection of the compensation site is consistent with those plans.

d. Site constraints, including a description of the constraints at the mitigation site that could affect the success of the mitigation project and strategies used to address each constraint. (Constraints may include factors outside of the control of the applicant, such as a primary water source for the mitigation wetland originating offsite, the potential for other landowners to alter the source, etc.).

4. Existing (Baseline) Conditions of the Mitigation Site. The following information must be provided regarding existing conditions of the mitigation site:

a. Historic and current land uses and zoning;

b. Known historic or cultural resources on the mitigation site;

c. Existing wetlands on or adjacent to the development site;

d. Maps showing current contours as surveyed. This is needed particularly when mitigation activities will alter ground elevations.

e. Description of the water regime;

f. Description of the soils;

g. Description of the vegetation;

h. Description of fauna using the site;

i. Position and function of the wetland(s)/stream(s) in the landscape;

j. Description of the functions provided by the wetland(s)/stream(s);

k. Wetland rating/stream classification;

l. Buffers; and

m. Water quality.

5. Mitigation Approach. The following information must be provided regarding the mitigation approach:

a. Mitigation sequencing, according to RZC 21.64.010.I, Mitigation Standards, Criteria, and Plan Requirements;

b. Project-specific goals. Identify the goal or goals of the compensatory mitigation project (e.g., provide adequate compensation for losses and degradation to wetland area and function);

c. Mitigation strategy, including a description in general terms of the strategies that will be used to achieve the goals;

d. specific goals, objectives, and performance standards for the site:

i. The goals and objectives for a mitigation site are intended to describe the ecological functions planned for the site and how those will be achieved. Performance standards are used to evaluate whether the goals and objectives are being met. Each objective shall be matched with one or more appropriate standards along with methods for monitoring them. In addition, maintenance must be designed for each objective.

ii. A description of the long-term goals of the mitigation project must be included and must address:

A. The size of the mitigation site;

B. Cowardin class, hydrogeomorphic class or subclass, and categorization (rating) for the wetlands to be restored, created, enhanced, and/or preserved.

C. Target functions and/or environmental process to be restored, created, enhanced, and/or preserved.

iii. A description of the objectives for each goal, with a minimum of at least one measurable objective for each goal must be included.

iv. Performance measures of each objective must be included.

6. Description of Mitigation Design. The following information must be provided regarding mitigation design:

a. Description of the water regime and how adequate amounts of water will be provided to support a wetland and/or description of enhanced stream design, including any in-water features;

b. Type of development (existing and proposed land uses);

c. Discussion of how the mitigation plan will compensate for lost and degraded functions. Provide rationale for each proposed function and describe the design features that would contribute to providing the function; and

d. Section drawings showing relationship of topography to water regime and vegetation.

7. Mitigation Plan Requirements. The following information is required for mitigation plans:

a. Orientation and scale (1 inch = 20 feet);

b. Existing and proposed elevation contours (2-foot contours);

c. Spot elevation for low points, high points, and structures;

d. Property boundaries;

e. On-site wetland boundaries (delineated and surveyed);

f. On-site ordinary high water mark (OHWM) boundaries for streams, and both OHWM and floodplain boundaries for Class 1 waters (delineated and surveyed);

g. Survey of benchmarks;

h. Location and elevation of soil borings or test pits;

i. Location and elevation of water elevation sampling devices, if applicable;

j. Location of soil to be stockpiled, if any;

k. Description of methods of erosion control and bank stabilization;

l. Buffer areas for the mitigation site and their boundaries;

m. List native plant materials. Provide a table that contains the following information:

Symbol

Scientific Name

Common Name

Size

Spacing

Quantity

Symbol


(Example)

Thuja plicata

Western Red Cedar

6 feet

See table below

10

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

i. Spacing: Triangular spacing shall be used to calculate plant density within mitigation areas (see table below);

Spacing

Multiplier

Planting Area Square Feet

Number of Plants

4 feet (Example)

.0725 (Example)

2,000 square feet (Example)

145 (Example)

4 feet

.0725

 

 

5 feet

.0465

 

 

6 feet

.032

 

 

8 feet

.018

 

 

10 feet

.0116

 

 

12 feet

.008

 

 

15 feet

.00515

 

 

ii. Size: All plants shall have following minimum size at installation:

A. Deciduous and Evergreen trees: minimum 5-gallon containers;

B. Medium and tall shrubs: minimum 2-gallon containers;

C. Groundcover: 1-gallon container (spaced at 18 inches on center);

D. Emergent plants: 10-cubic inch pots (spaced at 18 inches on center);

n. Other planting details (Balled and Burlapped (B&B), bare root, live stakes, etc.);

o. Other habitat feature details (rootwads, stone piles, snags, etc.);

p. Expected natural revegetation. From existing seed bank and natural recruitment from nearby sites;

q. Description of methods to control invasive species; and

r. Description of permanent protective features (fencing and signage).

8. Irrigation Plan. If temporary irrigation is used, a plan and details shall be submitted to and approved by the City’s Planning Department.

9. Monitoring Plan.

a. Monitoring and contingency plans shall be consistent with RZC 21.64.010.P, Monitoring Program and Contingency Plan. The monitoring program shall be used to determine the success of the mitigation project and any necessary corrective actions. Monitoring programs must comply with the City’s guidelines set forth in RZC 21.64.010.P.3. Monitoring methods and components shall be consistent with RZC 21.64.010.P.3.e, as outlined below:

i. Vegetation Monitoring: Methods shall include counts, photo points, random sampling, sampling plots, transects, visual inspections, and/or other means deemed appropriate by the Department and a qualified consultant. Vegetation monitoring components shall include general appearance, health, mortality, colonization rates, percent cover, percent survival, volunteer plant species, invasive weeds, and/or other components deemed appropriate by the Department and a qualified consultant.

ii. Water Quantity Monitoring: Methods shall include piezometers, sampling points, stream gauges, visual observation, and/or other means deemed appropriate by the Department and a qualified consultant. Water quantity monitoring components shall include water level, peak flows, soil saturation depth, soil moisture within root zone, inundation, overall water coverage, and/or other components deemed appropriate by the Department and a qualified consultant.

iii. Water Quality Monitoring: Methods shall include testing, plant indicators, and/or other means deemed appropriate by the Department and a qualified consultant. Water quality monitoring components shall include temperature, pH, dissolved oxygen, total suspended solids, total metals, herbicides, pesticides, and/or other components deemed appropriate by the Department and a qualified consultant.

iv. Wildlife Monitoring: Methods shall include visual sightings, aural observations, nests, scat, tracks, and/or other means deemed appropriate by the Department and a qualified consultant. Wildlife monitoring components shall include species counts, species diversity, breeding activity, habitat type, nesting activity, location, usage, and/or other components deemed appropriate by the Department and a qualified consultant.

v. Geomorphic Monitoring: Methods shall include cross sectional surveys, profile surveys, point surveys, photo-monitoring, and/or other means deemed appropriate by the Department and a qualified consultant. Monitoring components shall include location and effect of large woody debris, depth and frequency of pools, bank erosion, channel migration, sediment transport/deposition, structural integrity of weirs, and/or other components deemed appropriate by the Department and a qualified consultant.

b. A map of sampling locations and description of how the locations will be determined for each monitoring event.

10. Maintenance and Contingency Plans (Text on Plan Sheet). The following information is required for Maintenance and Contingency Plans:

a. Maintenance Plan (text);

b. Description of and reason for each maintenance activity planned; and

c. Contingency plan, including:

i. Initiating procedures; and

ii. Description of contingency funds.

11. Financial Assurances. The amount of the guarantees shall be based upon a detailed budget for implementation of the mitigation plan, including installation, monitoring, maintenance, and contingency phases for a minimum of five years.

12. Final Mitigation Plan Set. The applicant shall submit a final mitigation plan set prepared by a qualified consultant when filing for civil construction drawings review or building permit, whichever is applicable. The final civil drawings or building permit (as applicable) shall not be approved until the final mitigation plan and bonds have been approved and accepted by the City.

13. Record Drawings. Wetland/Stream mitigation record drawings shall be submitted to the City along with engineering record drawings. A copy of the mitigation record drawings shall be submitted to the Planning Department. The record drawings shall include a table identifying the following information for each wetland or stream on-site:

Wetland(s) and/or Stream(s)

Area (square feet) of undisturbed wetland/stream

Area (square feet) of mitigated wetland/stream

Area (square feet) and width (feet) of buffers

Linear feet (l.f.) along the centerline of undisturbed streams

Linear feet (l.f.) along the centerline of relocated stream, if any

Wetland A (Example)

560 square feet

560 square feet

625 square feet, 25-foot buffer

N/A

N/A

 

 

 

 

 

 

 

 

 

 

 

 

Related Forms:

Habitat Unit Assessment Form

Stream Summary Sheet

Wetland Summary Sheet

Wetland Data Form

Wetland Rating Form

Effective on: 6/18/2018